Drag-saw.



A. T. STIMSON.

DRAG SAW.

vAPPLIOAJIION FILED MAYQ, 1912.

Patented May 20, 1913.

3 SHEETS-SHEET 1.

Amm

WlTNEssES ATTQRN EY coLUMBlA PLANOGRA'PH CULWASHINUTON, n. c.

" VYA. 'I'. STIMSON.

DRAG SAW.

APPLIoATIoN FILED MAYQ, 1912.

Patented May 20, 1913.

3 SHEETS-SHEET 2.

ATTO R N EY cnLuMBIA PLANOURAPH co., WASHINGTON. D. c.

A; T. STIMSON.

DRAGSAW. APPLICATION FILED MAYS, 1912.

Patented May 2o, 1913.

INVENTOR fz 3 SHBBTS-SHBET a.

wlTNEssEs -im m mw ATTO RN EY COLUMBIA PLANODRAPH c Il ITED STATESFATENT OFFICE.

ALFRED THOMAS STIMSON, OF LODI, CALIFORNIA.

DRAG-SAW.

Specification of Letters Patent.

Patented May 20, 1913.

Application led May 9, 1912. Serial No. 696,173.

.be readily applied to a log in operative relation thereto, and whichwill rapidly and automatically cut the log after the initial adjustmentshave been made.

In accordance with the present invention there is provided a supportingframe with means for securingthe frame to a log in such a manner thatthe saw may be brought into proper relation to the log irrespective ofirregularities therein, and also to provide driving means whereby thesaw will have a movement similar to a hand operated saw and willautomatically feed until the logis severed,. the structure beingespecially adapted for use in connection with a power means, such as asuitable type of explosion engine.

The invention will be best lunderstood from a consideration of thefollowing detailed description, taken in connection with theaccompanying drawings forming a part of this specification, with thefurther understanding that the invention is susceptible of differentpractical embodiments which may differ in immaterial respects from theshowing of the drawings, wherefore the inf vention is not confined toany strict conformity with the structure illustrated in the drawings butmay be changed and modified so long as such changes do not mark adeparture from the salient features of the invention.

In the drawings IFigure l is a side elevation of the machine inoperative relation tion in the plane of the cut.

`both for lightness and strength.

tion on the line 5 5 of Fig. 2 with parts omitted. Fig. 6 is aperspective view of a portionof a latch mechanism employed in connectionwith the machine. Fig. 7 is a perspective view of a portion of the latchmechanism and actuating parts therefor `Dartlv omitted from Fig. 6.

`Referring to the drawings, there is shown side members 1, 2 and crossmembers 3, 4,

of a frame of general rectangular outline, and which may be made ofstructural steel For conveniencel of description that end of the framewhich, as will hereinafter appear, is

presented toward the log to be sawed, will be designated the front end,while the other end of the frame will be designated the rear end. Theside members 1 and 2 diverge near the front end of the frame andterminate in more widely spaced portions 5, 6 than the main portion ofthe frame. The members 5 and 6 are suitably stiffened by braces 7extending to one of the cross pieces 3 and other bracings may be used asthe exigencies of the structure may demand, large structures requiring agreater amount of bracing than small ones.

Made fast to the end 6 of the side member 2 is a stabbing point 8designed to enter a log, indicated in the drawings at 9a, so as to holdthe portion of the frame carrying the point 8 firm with relation to thelog. The extension 5 of the side member 1 is also provided with astabbing point 9 held to the member 5 by screws 10 extending throughslots 11 in the body of the stabbing point 9,

so that the latter may be moved lengthwise of the member 1 to the extentpermitted by the slots 11 and when thedesired adjustment is reached thestabbing point may be fastened to the end '5 by tightening the screws10. That end of the body member of the stabbing member 9 remote from thepoint thereof has an angle extension 12 suitably threaded for thepassage of the threaded end 13 of a rod 14, which rod has bearings in asuitable number of angle brackets 15 fast to the member l, while the endof the rod 14 remote from the threaded end 13 is squared or otherwisesuitably shaped, as indicated at 16, for the application of asuitablertool, whereby the rod may be rotated to cause lengthwiseadjustment of the stabbing point 9. The rod 14 is held againstlongitudinal movement by suitable collars 17 which may engage oppositesides of one of the brackets 15.

The side members 1 and 2 carry 'bearings 18, 19, respectively, for ashaft 20, and on the bearings there is mounted a drum. 2l which may beapproximately as long as the space between the side members 1 and 2. Thedrum carries at an appropriate point the ratchet wheel 22 having acapstan hub 23 provided with appropriate holes for the insertionofcapstan bars, whereby the drum may be turned as is found desirable. Theratchet wheel 22 and hub 23 is provided with axial extensions 24 for thepassage of set screws 25 by means of which the ratchet wheel is fastenedat any appropriate point on the drum 21. A pawl '26 is made fast to thecross member 3 and is designed to engage the teeth of the ratchet wheel22, this pawl being indicated as a spring pawl, and may be shaped toproperly hold the ratchet 22. Secured to the drum 21 is one end of achain 27, the other end of which carries a dog 28 designed to be driveninto the log 9a. Made fast to the bearings 18 and 19 are respective ears29 to which are hooked t-he free ends of legs 30 of a yoke formed at thejunction points of the legs into a hook 31 designed to receive a chain32 having at the end remote from the yoke a dog 33 which may be driveninto the log 9a, the arrangement being such that the dog- 28 may bedriven into the lower portion of the log` as it lays on the ground,while the dog 33 is driven into the upper portion of the log. By hookingthe appropriate link of the chain 22 in the hook 31 after the dog 33 hasbeen driven in place, and turning the drum 21 after the dog 28 has beendriven into the log, the main frame may be drawn toward the log, so thatthe stabbing points 8 and 9 are forced thereinto to the desired extentto hold the parts firmly in place, such adjustments of the stabbingpoint 9 being made as are necessary to bring the several parts into theproper relation to the log. As a further holding means the side member 2is provided with an eye 34 to which is hooked one end of a rod 35including a turn buckle 36, the other end of the rod 35 having a portion37 designed to be driven into the log, the turn buckle 36 permitting anydesired strain to be put upon the rod 31.

The shaft 20 is extended through the bearing 19 and for a distancebeyond that side of the side member 2 remote from the side member 1 andthere the shaft 5 has fast thereto a gear wheel 38 of appropriate sizeengaged by a pinion 39 on a shaft 40, which shaft may represent thepower shaft of an explosion engine or a shaft of gearing between anexplosion engine and the wheel 38. To facilitate the attachment of anexplosion engine to the frame of the machine the rear ends 0f themembers 1 and 2 are notched, as

indicated at 41, to provide for attaching bolts, whereby an explosionengine may be made fast to the frame members 1 and 2.

The gear wheel 38 is shown in Fig. 3 as .provided with a recess orchamber 42 in vwhich are lodged gear wheels 43,- 44 and 45,

respectively, the train of gear wheels being in substantially radialrelation to the gear wheel 38. The gear wheel 43 is concentric rwith theshaft 20, but is not made fast there- Ito, being secured to anothermember to be described. The gear wheels 44 and 45 are mounted upon stubshafts 46 and 47, respectively, each having bearings at one end in thegear wheel 38 and at the other end in 1a cap plate 48 made fast to thegear wheel 38. The stub shaft 47 is extended a distance beyond the outerface of the gear wheel 38 and there carries a cam 49 and an arm 50, thelatter being in the nature of a crank arm carried at one end by theshaft `elastic bearing member 57 in the path of the cam 49, so that ateach revolution of Vthe shaft 47 to which the` gear wheel 48, cam

49 and arm 50 are made fast the -cam 49V engages the spring member 57,-thereby holding the parts against displacement, which might otherwiseproduce vibration of the saw were they not so held during the operationof the machine.

Fast to the inner face of the gear wheel 43 is the laterally enlargedend 58 of an arm, 59 radial with relation to the gear wheel 38. This armextends to one side of a segmental rack bar 60 fast at one end to theside member 2 and at the other end to a post 6l erected on the sidemember 2 at an appropriate point back of the shaft 20, and in order tostien the side member-2 vthe post 61 has a downward continuation 62 fromwhich braces 63 and G4 extend to opposite ends of the side member 2after the mannerof a truss, thus greatly strengthening the portion ofthe main frame withstanding the greater part of the strain.

Fast to the arm 59 adjacent to and on opposite sides of the rack 60 arespacer blocks 65 connect-ed by a plate 66 in such manner as to form achannel throughwhich the rack bar extends. This rack bar is provided onopposite edges with rack teeth 67, 68, respectively, these rack teethbeing oppositely directed. Held to the bar 59 by a strap 69 is a slidingpawl 70 terminating in an angle tooth 71 adapted to engage in any of theteeth 68, the pawl being located on what may be termed the upper edge ofthe arm 59. Similarly arranged on the lower edges of the arm 59 and heldthereto by the same strap 69 is another sliding pawl member 72 longenough to extend around the front edge of the rack, and is there formedwith a tooth 73 adapted to engage any one of the ratchet 4teeth 67. Thefree end of the tooth 73 carries a pin 74, while the plate 66 carries apin 75, the two pins 74 and 75 receiving the two ends of a spring 76tending to hold the toot-h 73 in engagement with the ratchet teeth 67,but yielding to the passage of these teeth by the tooth 73.

Secured to the sliding pawlis one end of a lever 77 pivoted to the arm59, and the other end of this lever has one end of a spring 78, theother end 79 of which engages the arm 59, such spring being shaped toyield to longitudinal movements of the pawl 7 O and also being operablefrom the arm 59 for a purpose which will hereinafter appear.

The sliding pawl 7 2 is provided at an appropriate point with a notch 80into which engages a finger 81 on a shaft 82 having bearings in abracket 83 carried by the arm 59 at a point adjacent to the free end ofthe arm. The shaft 82 also carries an arm 84 having at its free end, foradjustment, a laterally extended eye 85 traversed by a bolt 86 in turncarried by another arm 87 one end of which is pivotally supported by theshaft 82 whichv proj ect-s for the purpose beyond the bracket 83, thearm 87 being held to the shaft by a nut 88 applied to the correspondingend of the shaft 89.. This arm carries at its free end a weight 89shaped to embrace at its lower edge the upper edge of the saw 56, andthis weight is also formed with a pocket for a mass 90 of suitablematerial, such as waste or the like, capablevof receiving and 'retaininglubricant, so that the saw may reciprocate with relation to the weight89 without undue friction. A spring 91 is made fast at one end to theweighted end of the arm 87, and at the other end to a finger 92 fast tothe bracket 83, the tendency of the spring 91 being to hold the weight89 in engagement with the back edge of the saw.

The `tree end of the arm 59 has an extension 93 from which extendconnected links 94 to the arm 87 to sustain said arm and limit itsmovement in a direction toward the saw. The free end of the arm 59 isalso provided with a handle 95 whereby the arm i may be convenientlymanipulated.

Let it be assumed that the machine has been adjusted to a log with thearm 59 elevated to an extent permitting the saw 56 to engage the top ofthe log, and let it further be assumed that the saw is at the extreme ofits forward stroke as shown in Fig. 1. lf, now, the driving power bestarted to cause f gear wheels 43 and 45.

rotation of the gear wheel 38 in a counterclockwise direction as viewedin Fig. 1, its direction of rotation being indicated by an arrow in saidligure, the shaft 47 is given an orbital rotation about the axis of theshaft 20 and is also given a rotative movement about its own axis, sincethe gear wheel 43 is under the conditions assumed substantiallystationary and the gear wheel 44 acts simply as a direction changingidler. Assuming the gear wheel 38 to be moving counter-clockwiseand thegear wheel 43 to be standing still, the idler gear wheel 44 will on therotative movement of the gear wheel 38 in a counter-clockwise directionbe moved also in a counter-clockwise direction about its own axis,wherefore motion is imparted to the gear wheel 45 in a clockwisedirection, and this same movement is imparted to the arm 50. At the sametime, however, the shaft 47 is moving in a coimter-clockwise directionorbitally about the shaft 20, wherefore the wrist pin 51 is caused tomove in a very flat ellipse, indicated approximately by the dot and dashline 96 in Fig. 1. The very fiat elliptical path of the wrist pin 51 isdue to the fact that the gear wheel 45 is one-half the diameter of thegear wheel 43 and the wrist pin 51 is spaced from the axis of the gearwheel 45 a greater or less distance than the separation of the axis ofthe This means that the saw 56 is reciprocated by the rotative movementof the gear wheel 38 in a direction closely approximating a straightline, but from such straight line to an extent determined by the minoraxis of the fiat ellipse,

Yso that the saw has a rocking movement imparted to it during itsreciprocations, thus serving to clear the saw kerf from saw dust, movingit from the center toward and from both ends ofthe cut. This rockingmovement is also utilized to cause the feeding of the saw as it cutsinto the log. Each time the weighted end of the arm 87 drops the arm 84moves wit-h it a short distance, but sufficient to cause the finger 81to move the pawl 72 to an extent to carry the tooth 73 out of engagementwith a ratchet tooth 67, whereupon the weight of the parts will causethe arm 59 to drop, but only for a very limited distance, since theparts are still held by the saw. This dropping movement is, of course,participated in by the pawl 70, but the tooth 71 will yield to the teeth68, being held thereto only by the spring 78. Before the parts can dropmore than the dist-ance of one tooth the saw has rocked sufficiently tocause the tooth 73 to move toward the rack 60, so that the droppingmovement is ultimately arrested by the engagement of the tooth 73 withthe next lower tooth 67 in order. The movement of the arm 59 causes acorresponding rotative movement of the gears 43, 44 and 45, thusreadjusting the reciprocating movement of the saw to the new position ofthe parte, so that the saw is kept in line with the actuating mechanismat all times while the log is being severed. Suppose, now, that it isdesirable to lift the saw to its high position, it is only necessary torelease the end 7 9 of the spring 78 from the arm 59 when the pawl 70may be moved lengthwise of the arm 59 until its tooth 7l is out of thepath of the teeth 68, and then the arm with the saw and other parts car`ried by the arm may be lifted to as high a position as desired, eitherby reversing the engine or disconnecting it from the gear wheel 38, sothat the saw may be lifted without being reciprocated. On the return ofthe end 7 9 of t-he spring 7S into engagement with the arm 59 the saw isready to make a new cut.

Vhat is claimed is l. In a drag saw, a gear wheel fixed againstrotation, a radially disposed train of gearing in mesh with and mountedto revolve about the gear wheel, a crank arm carried by and fast to thegear of the train of gearing remote from the first-named gear wheel, anda saw secured to the crank arm for actuation thereby, the crank arm andgearing being' related to cause the end of the crank arm secured to t-hesaw to describe an elongated flat ellipse.

2. In a drag saw, a rotatable member for the reception of power, aradially disposed train of gearing carried by the rotatable member withone end member of the train of gearing concentric with the axis ofrotation of said rotatable member and the other end member provided witha crank arm fast thereto, a saw provided with means for attachment tothe crank arm for actuation thereby, and feeding means for the sawconnected to the axially disposed gear of the train of gearing' andholding the said gear against participation in rotative movements of therotatable member.

3. In a drag saw, means for imparting a reciprocatory and rockingmovement to the saw, and means for feeding the saw to the workcomprising a ratchet member, an arm movable along the ratchet member inoperative relation thereto, a pawl carried by the arm in position toengage the ratchet member, a rock shaft carried by the arm and providedwith engaging means for the pawl, a rock arm carried by the rock shaftand movable therewith, and another rock arm movable independently of therock shaft and provided with means for engaging the saw, said secondnamed rock arm being connected to the iirst named rook arm for actuatingthe latter.

4. A drag saw provided with a train of gearing, a support for one endmember of the train of gearing about which said member may move axially,an arm connected to the other end member of the train of gearing andprovided with means for attachment to a saw, and feeding means for thesaw comprising a relatively fixed rack, an arm carried by the firstnamed end member of the train of gearing, releasable connections betweenthe arm and the rack, rock members carried by the arm in position to beengaged by the saw and in turn controlling the engagement of the armwith the rack, and means for rotating the train of gearing about theaxis of the end member of the train to which the arm is connected.

5. A drag saw provided with means for imparting reciprocatory rockingmotio-n to the saw, and means for'feeding the saw to the work comprisinga relatively fixed ratchet member, an arm in operative relation to andmovable with reference to the ratchet member, pawls carried by the armand adapt-ed to engage t-he ratchet member, a rock shaft carried by thearm and provided with an engaging means for one of the pawls to move thelatter to release position, a rock arm on the shaft, another rock armmovable with relation to the irst rock arm and provided with adjustingmeans fo-r the first named rock arm, and saw engaging means carried bythe second named rock arm.

G. A drag saw provided with a rotatable train of gearing having onemember relatively iixed against rotation and the other members revoluble`about the axis of the first named member, the said train of gearingbeing in substantiallv radial relation to the axis of revolution of thetrain, connections carried by and fast to the outermost member of thetrain of gearing for actuating a saw, and intermittently acting holdingmeans in operative relation to the outermost member of the train ofgearing.

In testimony, that I claim the foregoing as my own, I have heretolaiiixed my signature in the presence of two witnesses.

ALFRED THOMAS STIMSON.

IVitnesses:

IV. R. STiMsoN, J. W. EDDLEMAN.

Copies of this patent may be obtained for ve cents each, by addressingthe Gommissonexl of Patents. Washington, D. C.

